Systems and methods for providing attestation of data integrity

ABSTRACT

Disclosed is a method of establishing secure communications. The method includes receiving an attestation parameter associated with a first peer in a potential peer-to-peer communication, adding the attestation parameter to an MACsec Key Agreement (MKA) protocol key exchange, transmitting the key exchange from the first peer to a second peer in the potential peer-to-peer communication and upon a validation of the attestation parameter by the second peer, enabling secure communication between the first peer and the second peer.

TECHNICAL FIELD

The subject matter of this disclosure relates to an extension of the MACSecurity Key Agreement protocol to add a feature of validating theintegrity of data to establish trust between two peers or other devicesin a secure network environment.

BACKGROUND

The Media Access Control Security (MACsec) protocol is an 802.1AE IEEEindustry standard security technology that provides securecommunications for traffic between Internet links. MACsec providespoint-to-point security on Internet links between directly connectednodes and is capable of identifying and preventing most securitythreats, such as denial of service, intrusion, man in the middle,masquerading, passive wiretapping and playback attacks.

MACsec allows administrators to secure an Ethernet link for almost alltraffic, including frames from the Link Layer Discovery Protocol (LLDP).Link Aggregation Control Protocol (LACP), Dynamic Host ConfigurationProtocol (DHCP), Address Resolution Protocol (ARP), and other protocolsthat are not typically secured on an Ethernet link because oflimitations with other security solutions.

MACsec provides security through the use of secured point-to-pointEthernet links. The point-to-point links are secured after matchingsecurity keys are exchanged and verified between the interfaces at eachend of the point-to-point Ethernet link. The key can be user-configuredor can be generated dynamically, depending on the security mode used toenable MACsec. The key exchange for MACsec leverages the MACsec KeyAgreement (MKA) protocol, based on the IEEE 802.AX-REV specification foradding new capabilities to specifically support MACsec key exchangebetween two or more stations. The existing MACsec association relies onpeer authentication to establish the session.

Once MACsec is enabled on a point-to-point Ethernet link, all traffictraversing the link is MACsec-secured through the use of data integritychecks and, if configured, encryption. The data integrity checks verifythe integrity of the data. MACsec appends an 8-byte header and a 16-bytetail to all Ethernet frames traversing the MACsec-secured point-to-pointEthernet link, and the header and tail are checked by the receivinginterface to ensure that the data was not compromised while traversingthe link. If the data integrity check detects anything irregular aboutthe traffic, the traffic is dropped.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the above-recited and otheradvantages and features of the disclosure can be obtained, a moreparticular description of the principles briefly described above will berendered by reference to specific embodiments thereof which areillustrated in the appended drawings. Understanding that these drawingsdepict only exemplary embodiments of the disclosure and are nottherefore to be considered to be limiting of its scope, the principlesherein are described and explained with additional specificity anddetail through the use of the accompanying drawings in which:

FIG. 1 illustrates the canary stamp approach:

FIGS. 2A-2C illustrates example networking environments associated withattestation;

FIG. 2D illustrates an example network environment associated with anaspect of this disclosure:

FIGS. 2E-2F example flows for providing proof of packet transit throughuncompromised nodes, in accordance with some examples;

FIG. 3 illustrates the existing SecTAG format;

FIG. 4A illustrates the SecTAG format:

FIG. 4B illustrates the MAGsec TCI and AN Encoding;

FIG. 5 illustrates a method embodiment;

FIG. 6 illustrates an example network device in accordance with variousexamples; and

FIG. 7 illustrates an example computing device architecture, inaccordance with some examples.

DETAILED DESCRIPTION

Various embodiments of the disclosure are discussed in detail below.While specific implementations are discussed, it should be understoodthat this is done for illustration purposes only. A person skilled inthe relevant art will recognize that other components and configurationsmay be used without parting from the spirit and scope of the disclosure.

Overview

Additional features and advantages of the disclosure will be set forthin the description which follows, and in part will be obvious from thedescription, or can be learned by practice of the herein disclosedprinciples. The features and advantages of the disclosure can berealized and obtained by means of the instruments and combinationsparticularly pointed out in the appended claims. These and otherfeatures of the disclosure will become more fully apparent from thefollowing description and appended claims, or can be learned by thepractice of the principles set forth herein.

The existing MACsec does not provide any mechanism to verify if one ofthe peers or devices in the communication has been compromised. Forexample, hardware, firmware, software of the peer could be tamped withor become compromised during the lifetime of the MACsec session orbefore the session. This disclosure proposes to extend the MACsec KeyAgreement (MKA) protocol and the MACsec protocol to support validationof attested integrity data to thereby establish trust between two ormore peers in the secure network environment to establish and maintain aMACsec session for data exchange. The process can also provide andconfirm the integrity of any node or router within the secure networkenvironment that is routing packets from one node to another node. Thedesire is to confirm the current state of the component in terms of oneor more of its hardware, firmware, software or other parameterassociated with a device in a communication. This can be done in oneaspect by adding a canary stamp or similar attestation data to a MACsecprotocol. In this scenario, when devices are performing an initialhandshake to determine whether they can communicate or whether tocontinue communicating with each other, a canary stamp in a MACsecprotocol exchange can include the attestation information. The devicescan then make determination regarding the status of the other devicebased on the attestation information.

These principles can also be used to provide a confirmation of anidentity of a device that is to be part of a secure communication.

An example method includes receiving an attestation parameter associatedwith a first peer in a peer-to-peer communication, adding theattestation parameter to a MACsec Key Agreement (MKA) protocol keyexchange, transmitting the key exchange from the first peer to a secondpeer in the peer-to-peer communication and upon a validation of theattestation parameter by the second peer, enabling secure communicationbetween the first peer and the second peer.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Disclosed herein are systems, methods, and computer-readable media forinnovations which focus on the ability to improve the use of theavailable bandwidth in a certain modes such as a low bandwidth mode inwhich a first device communicates with the second device. Other modescan apply as well, such as where a user according to an agreement shouldreceive more bandwidth or has a higher priority than other users.

This disclosure proposes an extension of the MAC Security Key Agreement(MKA) and MACsec protocols to support validation of an attestedintegrity of data to establish trust between 2 or more peers in a securenetwork environment to establish and maintain a MACsec session for dataexchange.

The IEEE 802.1AE MAC Security Protocol, or MACsec, is a MAC layer or alink layer encryption scheme and offers encryption equal to that of theEthernet port rates (10/100/1000 Mbps) by directionally regardless ofthe packet size. The protocol executes the encryption function in thephysical layer (PHY) of the Ethernet port. Unlike IPsec, which istypically performed on a centralized application-specific integratedcircuit (ASIC) optimized for accelerating encryption, the MACsecprotocol is enabled on a per report basis with no performance impact.

FIG. 1 illustrates the basic approach. The concepts disclosed hereinbuilds upon the idea of the “canary stamp” or attestation parameter setwhich adds an in-depth layer of attestation information into IEEE 802.1AE MACsec, specifically leveraging the control plane key exchangeprotocol of MACsec Key Agreement (MKA) protocol, extending the MKA tosupport transporting attestation information/messages between two ormore MACsec stations 102, 106 communicating via a network 104 in anoverall system 100. Furthermore, the canary stamp concept provides earlyinsight into evidence of any device tampering, and given thelevel/threshold of evidence, per the operator's discretion, the link,including key material can be immediately terminated, eliminating therouting device as a possible transmitting node in the network.

FIGS. 2A-2F are next discussed which provide a more detailed discussionof various attestation approaches for providing an attestationconfirmation for a node within a network. The node can be any component,router, source node, destination node, and so forth that transmits,routes, and/or receives packets. Because any of these nodes might beparticipating in a secure communication according to the MKA protocol,this discussion provides underlying information about how theattestation data can be obtained and used. Following the discussion ofcanary stamps and FIGS. 2A-2F, this disclosure will turn to FIG. 3 andresume the focus on the use of the attestation parameters in the contextof the MKA protocol.

The following is a discussion introducing the use of attestationtechniques for confirming that a node or device in a network has notbeen compromised. The technologies herein can provide proof of packettransit through uncompromised network nodes, to ensure that packets havenot traversed untrusted or compromised nodes that can harm or improperlyaccess the packets and associated data. In some examples, thetechnologies herein can implement proof-of-transit (POT) and attestationtechniques to confirm the integrity of a node, verify that traffictraverses a defined set of nodes, and verify that such nodes have notbeen compromised. In some cases, such POT and attestation techniques canimplement canary stamps (e.g., tokens or metadata elements containing orreflecting security measures taken at one or more nodes).

This initial discussion of systems and technologies for providingexplicit verifiable proof of integrity of network nodes traversed bypackets will be a foundation for the later discussion on MKA protocols.

A computer network can include different nodes (e.g., network devices,client devices, sensors, and any other computing devices) interconnectedby communication links and segments for sending data between end nodes.Many types of networks are available, including, for example, local areanetworks (LANs), wide area networks (WANs), software-defined networks(SDNs), wireless networks, core networks, cloud networks, the Internet,etc. When data traffic is transmitted through one or more networks, thedata traffic typically traverses a number of nodes that route thetraffic from a source node to a destination node.

While having numerous nodes can increase network connectivity andperformance, it also increases security risks as each node that a packettraverses introduces a risk of unauthorized data access andmanipulation. For example, when a packet traverses a node, there is asecurity risk that is introduced which can result from the node beingpotentially compromised (e.g., hacked, manipulated, captured, etc.). Asa result, compliance, security, and audit procedures can be implementedto verify that network users, devices, entities and their associatednetwork traffic comply with specific business and/or security policies.

When sensitive information is transmitted through nodes in a network,such as in battlefield, banking settings, and healthcare settings, suchtraffic should be sent through uncomprised nodes to prevent access to,leakage of, or tampering with the data and sensitive information carriedby that traffic. If an attacker gains access to a device via someexploit, previous protection and encryption approaches for networkinterfaces are generally ineffective at mitigating or addressing suchunauthorized access and resulting damage.

Proving that network traffic complies with specific policies can involveproving in a secure way that the traffic has traversed a well-definedset of network nodes (e.g., firewalls, switches, routers, etc.) and thatsuch network nodes have not been modified or compromised. This can helpensure that the network nodes have performed their expected or intendedactions (e.g., packet processing, security or policy complianceverification, routing, etc.) on the packet and that the packet hastraversed the network nodes.

Some security approaches can aim at removing any implied trust in thenetwork used for connecting applications hosted on devices to cloud orenterprise hosted services. Moreover, some security approaches can beimplemented to verify the trustworthiness (e.g., the integrity,identity, state, etc.) of the network and/or nodes traversed by packets.In some cases, certain verification checks can be implemented tovalidate or verify that traffic has traversed a specific set of nodesand that such nodes are trusted and uncompromised. In some examples,certain Proof-of-Transit (POT). Trusted Platform Module (TPM),attestation, or proof of integrity approaches can be implemented toverify or validate the trustworthiness of a node in a network.

POT can enable a network user or entity to verify whether traffictraversed a defined set of network nodes. Attestation, as furtherdescribed below, can also be used to verify the integrity of a node. Insome cases, the approaches herein can integrate both to offer a secureapproach that allows network users or entities to verify that traffichas traversed a defined set of nodes and that such nodes have not beencompromised.

In some cases, TPM can be implemented to collect and report the identityof hardware and software components in a platform to establish trust forthat platform. A TPM used in a computing system can report on thehardware and software of the system in a manner that allows verificationof expected behavior associated with that system and, from such expectedbehavior, establishment of trust. The TPM can be a system componentcontaining state that is separate from the host system on which the TPMreports identity and/or other information. TPMs can be implemented onphysical resources (indirectly or directly) of the host system. In someexamples, a TPM component can have a processor and memory such as RAMROM and/or flash memory. In other implementations of a TPM, a hostprocessor can run TPM code while the processor is in a particularexecution mode. Parts of system memory can be partitioned by hardware toensure that memory used by the TPM is not accessible by the hostprocessor unless the host processor is in the particular execution mode.

In some cases, trusted computing (TC) implementations, such as TPM, canrely on Roots of Trust. Roots of Trust can be system elements thatshould be trustworthy because misbehavior by such system elements maynot be detectable. A set of roots can provide a minimum functionalitythat can sufficiently describe characteristics that affect a platform'strustworthiness. In some cases, determining if a Root of Trust isbehaving properly may not be possible; however, it may be possible todetermine how roots are implemented. For example, certificates canprovide assurances that the root has been implemented in a way thatrenders it trustworthy.

To illustrate, a certificate may identify the manufacturer and evaluatedassurance level (EAL) of a TPM. Such certification can provide a levelof confidence in the Roots of Trust used in the TPM. Moreover, acertificate from a platform manufacturer may provide assurance that theTPM was properly installed on a system that is compliant with specificrequirements so the Root of Trust provided by the platform may betrusted. Some implementations can rely on three Roots of Trust in atrusted platform, including Root of Trust for Measurement (RTM), Root ofTrust for Storage (RTS), and Root of Trust for Reporting (RTR).

The RTM can send integrity information, such as integrity measurements,to the RTS. Generally, the RTM can be a processor controlled by a CoreRoot of Trust for Measurement (CRTM). The CRTM is the first set ofinstructions executed when a new chain of trust is established. When asystem is reset, the processor (e.g., RTM) can execute the CRTM, whichcan then send values that indicate its identity to the RTS. Thus, insome cases, the starting point for a chain of trust can be establishedin this manner.

As previously noted, the TPM memory can be shielded from access by anentity other than the TPM. Since the TPM can be trusted to preventunauthorized access to its memory, the TPM can act as an RTS. Moreover,the RTR can report on the contents of the RTS. An RTR report can be adigitally signed digest of the contents of one or more values in a TPM.

Attestation is another example trusted computing approach that can beused to verify the integrity of a node. Attestation can be applied to anode, such as a router or switch, to review logs from connected devices,such as Layer 1 (L1) or Layer (L2) connected devices, and maintain theselogs in trusted storage. These logs can be protected by embedding aprivate key into every trust anchor produced for a hardware device, andpublishing the device's public key as a certificate to adjacent devices.This peering device can then push log updates from trusted storageperiodically and/or on some log entry event. Reviewing any providedsigned logs can provide an understanding of the current trustable stateof a peer device. Moreover, by looking back at the set of transactionswhich have occurred since boot time, a determination can be maderegarding the trustworthiness of the information which that peer deviceis asserting.

In some examples, canary stamps, which can refer to tokens or metadataelements containing security measurements or evidence, can be used toprovide verifiable evidence of device trustworthiness (e.g., integrity,state, etc.). Such verifiable evidence can be appended or included inpackets transmitted by nodes on a network. The canary stamps can thus beused to evaluate the trustworthiness of a node(s) and react accordingly.For example, a device or entity can review a canary stamp associatedwith a node to determine that the node should not be trusted and adjusta network policy to mitigate possible damage. The details in thedisclosure below provide an alteration to the MKA protocol to include acanary stamp or similar attestation parameter for identifying securenodes or secure communications.

In some implementations, dedicated cryptoprocessors, such as a processorin a TPM platform, can take measurements to attest to thetrustworthiness (e.g., identity, integrity, etc.) of a node and itsenvironment (e.g., software, hardware, operating system, runningbinaries, firmware, etc.). These measurements include evidence that thenode is in a safe state. In some cases, these measurements can beprovided through canary stamps, as previously described. However, areceiver of such evidence should be able to certify that the evidence isfresh, as the evidence can become stale thereby potentially reducing itseffectiveness in reflecting the current trustworthiness of a node. Forexample, without ensuring freshness of such evidence, an attacker has anopening to inject previously recorded measurements and asserting what isreplayed as being current.

Some approaches can detect the replaying of old evidence via a “nonce”.A nonce is a random number that can be used to introduce randomness. Insome cases, a nonce can passed into a TPM and/or incorporated into acanary stamp. In some cases, a result provided by the TPM can include asignature based on the nonce. Since the nonce can be grounded in atransactional challenge/response interaction model, in some cases thenonce may be less effective with unidirectional communicationsoriginating from an attesting device. For example, a nonce may lesseffective with an asynchronous push, multicast, or broadcast message.

However, there are numerous use cases where a platform assessing whetherits peers are trustworthy is advantageous. Being able to perform aunidirectional attestation using an asynchronous push, multicast, orbroadcast message in conjunction with trusted binaries opens manypossibilities for platforms to assess whether their peers aretrustworthy. Detection of invalid attestations can trigger alarms orevents, reduction of network access from a suspect device, or can becomea part of Admission Control (e.g., IEEE 802.1X). Some platforms can beconfigured to support the unidirectional attestation mechanism.

Other freshness approaches can be based on trusted computingcapabilities, such as TPM. For example, a token can be generated whichallows external entities to validate freshness of asserted data based onthe state of internal counters within the TPM. This token can be used todetect replay attacks, and provide attestation for asynchronous pushmulticast, and broadcast messages. In some cases, such tokes can includecanary stamps. Such tokens can be referred to as canary stamps becauseeach signed measurement is like a stamp proving its authenticity, andlike a canary in a coal mine they indicate an early sign of trouble.

Various of the foregoing approaches can be combined with TPM-integratedcapabilities aimed at verifying that valid compute components, such asbinary processes, are running on a node. These capabilities can include,for example, Trusted Execution Environments (TEE) which provide runtimemalware protections, Authenticated Code Modules (ACM) which ensure thatonly digitally-signed code modules can be loaded into a processor, andthe like. These technologies can validate that a processor is runningknown software with a valid chain of binary signatures.

In some cases, canary stamps (e.g., tokens or metadata elements) can becreated by extracting current counters (e.g., clock, reset, restart)from a node's TPM, and incorporating such counters and security measurestaken from the node into a packet. In some examples, the currentcounters and/or security measures can be hashed with information withinan external TPM. The canary stamp can thereby provide a non-spoofabletoken or metadata element, which can bind continuously incrementingcounters on an attestee with a known external state. Any resetting ofthe TPM counters is visible in any subsequent TPM queries, and anyrestarting of a platform is also exposed in subsequent TPM queries.Within these bounds of reset and restart, the TPM's time ticks countercontinuously increments. Therefore, any push of attestee TPM informationwhich includes these counters can be determined to have occurredsubsequent to any previously-received measurement. Also, if the resetand restart counters have not changed, the incremental time since anyprevious measurement can also be known.

In some cases, a large amount of information that should be trusted bynetwork peers may not be contained within the TPM's ProgramConfiguration Registers (PCR). As a result, indirect methods ofvalidating that a node has not been compromised can be applied.

The receipt of canary stamps can mean that a receiver should have theoption of verifying the information. In many cases, such verificationcan be performed without the need of supplementary evidence being sentwith the canary stamp. Moreover, in non-controller based or centralizedimplementations, the verification steps do not have to occur at thereceiver.

In some integrity verification implementations, a controller or devicecan implement an integrity verification application. The integrityverification application can be designed to recognize change events andevaluate known good values, which allow evaluation of a boot-integritystamp and a running process binary signature stamp based on, forexample. TPM counters, timestamps, nonces, and/or time tokens. On anydiscrepancy, a controller or centralized device can isolate acompromised node from its network peers by shutting down the interfacesof the node.

In some examples, one or more canary stamps (e.g., tokens or metadataelements) and/or verifications for integrity can be implemented, such asa measured-boot stamp (e.g., SHA1 hash over PCRs 0-7), a verified-bootstamp (e.g., which can verify that only recognized binaries wereexecuted when booting), a process-stamp (e.g., root-of-trust validatedthrough a process which is asserting a particular protocol orprotocols), a file-system stamp (e.g., all files within a vendordetermined set of directories), a log-integrity stamp (e.g., used toaugment existing integrity analytics and forensics), a configurationstamp (e.g., State of the current device configuration), etc. Someimplementations can achieve all or some of these stamps, depending onthe implementation. Moreover, in some implementations, all or some ofthese stamps can be implemented or achieved using a single or multiplestamps.

As previously explained. TPM provides methods for collecting andreporting the identity of hardware and software components in a platformto establish trust for that platform. TPM functionality can be embeddedin a variety of devices including mobile phones, personal computers,network nodes (e.g., switches, routers, firewalls, servers, networkappliances, etc.), and/or any other computing devices. Further,attestation can describe how the TPM can be used as a hardware root oftrust and offer proof of integrity of a node. Such integrity can includehardware integrity, software integrity (e.g., micro loader, firmware,boot loader, kernel, operating system, binaries, files, etc.), andruntime integrity.

In some cases, TPM and attestation can be implemented as describedherein to provide proof of integrity and proof of transit throughuncompromised nodes. In some examples, canary stamps (e.g., tokens ormetadata elements containing or reflecting security measures) are usedas previously mentioned to validate the integrity of a node and performcontinuous evaluation of node integrity. Thus, the canary stampsdescribed herein can be used to provide proof of transit throughuncompromised nodes.

In some examples, the canary stamp can be added as additional metadatato packets that traverse a network where proof of transit viauncompromised nodes is desired. Various strategies can be implementedfor transporting a canary stamp in a packet. In some cases, a canarystamp can be carried within an In-Situ (or in-band) Operations,Administration and Management (IOAM) data field.

In some implementations, a canary stamp can be carried IOAM trace data.For example, the canary stamp (e.g., the token or metadata) can becarried as part of an IOAM data field in a variety of encapsulationprotocols such as, for example and without limitation, iPv4, IPv6, NSH(Network Service Header), etc. In some cases, the canary stamp can becarried in an IOAM data field as an IOAM Trace option data element(e.g., with an IOAM Trace type for node integrity canary stamp). Acanary stamp or canary stamp digest can be added in the IOAM traceoption of a packet by each node that forwards the packet. In the presentdisclosure, attestation data is added to the MACsec and/or MKAprotocols.

When the packet reaches a node (e.g., the destination node and/or anintermediate node) that removes IOAM metadata (e.g., an IOAMdecapsulating node), the validity of a canary stamp in the packet can beverified to determine that the packet traversed uncompromised nodes. Insome examples, since canary stamps are time bound, the packet tracetimestamps defined in IOAM can be used to validate the canary stamp inthe time window the packet traversed that node.

Verification can be performed without placing a large transactional loadon the verifier or a device, such as a controller, that will ultimatelyvalidate the security measurements associated with the canary stamp.This is because canary stamp measurement values can often changeinfrequently. The verifier may only need to validate a canary stamp orcanary stamp digest carried within an IOAM data trace whenever thesecurity measurements associated with the canary stamp or canary stampchange (e.g., a verifier may only need to check with a controllerwhenever it sees a node's TPM extends a Platform Configuration Register(PCR) value which was not previously confirmed by the verifier).

In some cases, when only the time ticks within a signed canary stampincreases, only the signature of the canary stamp is validated. To dothis, the verifier may use the public key of any node which can place acanary stamp. Such signature validation can be done without using acontroller to verify stamp measurements.

In another example, a packet can carry IOAM POT data with spaceoptimization of canary stamp values. This example can leverage a newIOAM POT data field, which can carry canary stamp or a hash extend of acanary stamp and which can also carry canary stamp data across nodes. Insome cases, a canary stamp hash extend can be a similar method as aPlatform Configuration Registers (PCRs) extend operation performed byTPMs.

In some cases, the canary stamp hash extend can provide a one-way hashso that canary stamp recorded by any node cannot be removed or modifiedwithout detection. IOAM proof of transit option data for a canary stampdigest can be defined by a hash algorithm (e.g., 20 octets with SHA1, 32octets with SHA 256, etc.). In some implementations, each node along apath of the packet can forward the packet with a new or updated canarystamp digest. In some examples, the new or updated canary stamp digestcan be generated by a node as follows: IOAM canary stamp digest newvalue=Digest of (IOAM canary stamp digest old value II hash(canary stampof the node)), where the IOAM canary stamp digest old value can refer tothe canary stamp digest included in the packet by one or more previoushops.

Moreover, in some cases, a Per Packet Nonce (PPN), where PPN changes perpacket and is carried as another field within the IOAM metadata option,can be added to provide robustness against replay attacks. Toillustrate, in some examples, a PPN can be added as follows: IOAM canarystamp digest new value=Digest of (IOAM canary stamp digest old value IIhash(canary stamp of the node II PPN)). A node creating the new valuefor the IOAM canary stamp digest can thus take the value of any previousIOAM canary stamp digest, and extend/hash that value with the node'scurrent canary stamp. The result of the concatenation and hashing canthen be written into IOAM POT data (or other IOAM data fields) as thenew IOAM canary stamp digest.

At the verifier (e.g., the device verifying the canary stamp data), thesame operation can be performed over expected canary stamp valuescalculated for the nodes that are traversed in the time window when thepacket was forwarded. In some cases, a verifier can be an inline deviceor a centralized device. Moreover, in some examples, nodes that areexpected to be traversed can be identified using IOAM tracing, routingstate or by sending active probes. A match between the value of POT datacarrying a canary stamp digest and the expected canary stamp value canprove that the packet traversed through trusted or uncompromised nodes.

In some examples, one or more strategies can be implemented to optimizecanary stamp validation. For example, canary stamps can detect attemptsof a replay attack by embedding a nonce as well as TPM or TPM2 counters(e.g., clock, reset, restart). In some cases, this nonce can be part ofthe canary stamp and different from the PPN described above.

The nonce is relevant to a receiver as the interval from the nonce'screation time to the first stamp received by the verifier can define theinterval of freshness (e.g., the measurement is no older than thisinterval of freshness). From there, the TPM2 time ticks counter can beused to maintain that initial gap of freshness even without the deliveryof a new nonce.

In some implementations, to optimize canary stamp validation acrossnodes, the following approaches can be implemented to deliversynchronization information from a central component to each node andthe verifier. For example, a central server can broadcast or multicastcentralized nonce values (e.g., tracked random numbers). Each node canpick up the latest nonce and use it to attest a stamp value. A verifiercan know the freshness of a stamp it receives from each node. Thisfreshness can be the delta in time since that particular nonce wasissued. Subsequent attestations can use the incrementing time ticks toprove freshness from that initial time gap. In some cases, the issuingof new nonces can reset the time gap to a potentially shorter interval.

Moreover, in some cases, each node can embed attested time within itscanary stamp. To get attested time, a TUDA (Time-Based Uni-DirectionalAttestation) scheme such as the TUDA scheme described inhttps://datatracker.ietf.org/doc/draft-birkholz-i2nsf-tuda/, thecontents of which are incorporated herein by reference in theirentirety, can be used. This can result in the availability of both theattested time at a node, as well as the value of the TPM2 counters atthis node when a TUDA time-synchronization token was created. This caneliminate the use of a central nonce authority, but can increase thesize of the canary stamp as the nonce can be replaced by the TUDAtime-synchronization token. This approach may also implement a centraltimestamp authority as per TUDA. In some examples, for each hop, acanary stamp digest value can be: IOAM canary stamp digest newvalue=Digest of (IOAM canary stamp digest old value∥hash(canary stamp ofthe node∥TUDA time-synchronization token of the node)).

This approach can provide numerous benefits. For example and withoutlimitation, with this approach, a verifier can limit the number ofverifications by verifying the signature of a hop's time-synchronizationtoken only when it changes. Moreover, with this approach, there may notbe a time gap nonce changeover freshness when a first measurement isreceived.

Further, in some cases, this approach can be implemented without alsocarrying a PPN or without synchronizing a nonce across nodes aspreviously described.

Having provided an initial discussion of example concepts andtechnologies for providing explicit verifiable proof of integrity ofnetwork nodes traversed by packets, the disclosure now turns to FIG. 2A.

FIG. 2A is a block diagram of an example of networking environment 200Ain accordance with some implementations. While pertinent features areshown, those of ordinary skill in the art will appreciate from thepresent disclosure that various other features have not been illustratedfor the sake of brevity and so as not to obscure aspects of the exampleimplementations disclosed herein.

In this example, the networking environment 200A can include a network214 of interconnected nodes (e.g., 208A-N, 210A-N, and 212A-N). Thenetwork 214 can include a private network, such as a local area network(LAN), and/or a public network, such as a cloud network, a core network,and the like. In some implementations, the network 214 can also includeone or more sub-networks, such as sub-network 214A. Sub-network 214A caninclude, for example and without limitation, a LAN, a virtual local areanetwork (VLAN), a datacenter, a cloud network, a wide area network(WAN), etc. In some examples, the sub-network 214A can include a WAN,such as the Internet. In other examples, the sub-network 214A caninclude a combination of nodes included within a LAN, VLAN, and/or WAN.

The networking environment 200A can include a source node 202. Thesource node 202 can be a networking device (e.g., switch, router,gateway, endpoint, etc.) associated with a data packet that is destinedfor a destination node 216. The source node 202 can communicate withcandidate next-hop nodes 208A-208N on the network 214. Each of thecandidate next-hop nodes 208A-208N can be included within a respectiveroute between the source node 202 and the destination node 216.Moreover, in some cases, each of the candidate next-hop nodes 208A-208Ncan communicate with candidate second hop nodes 210A-210N in the network214. Each of the candidate second hop nodes 210A-20N can similarlycommunicate with candidate N-hop nodes 212A-212N in the network 214.

The networking environment 200A can also include an attestation routingorchestrator 204. The attestation routing orchestrator 204 cancommunicate with the candidate next-hop nodes 208A-208N. In someimplementations, the attestation routing orchestrator 204 can obtainattestation data (e.g., canary stamps, security measures, signatures,and/or metadata) or vectors from the candidate next-hop nodes 208A-208N.In some examples, the attestation routing orchestrator 204 can obtainadditional information from candidate second-hop nodes 210A-210N and/orcandidate N-hop nodes 212A-212N, and utilize the additional informationin selecting a particular candidate next-hop node for a packet. In someimplementations, the attestation routing orchestrator 204 can alsoobtain additional information from nodes that are more than two hopsaway (e.g., candidate third hop nodes, candidate fourth hop nodes,etc.).

The attestation routing orchestrator 204 can communicate with a verifiersystem 206. In some implementations, the attestation routingorchestrator 204 can obtain trusted state, such as a trusted imagevector, from the verifier system 206. The verifier system 206 caninclude a verified state repository 206A and one or more servers 206B.In some examples, the verified state in the verified state repository206A can include one or more verified images, verified securitymeasurements, verified settings, verified node data, and/or any otherverified trust or integrity data. In some implementations, the verifiedstate in the verified state repository 206A can include one or moretrusted states or image vectors that are known with a degree ofconfidence to represent uncompromised states or images (e.g., states orimages that have not been hacked, attacked, improperly accessed, etc.).

As will be described in great detail with reference to FIG. 2D, in somecases, the attestation routing orchestrator 204 can select and direct adata packet to a particular candidate next-hop node of the candidatenext-hop nodes 208A-208N based on a trusted state or image vector andthe attestation states or vectors. Moreover, the attestation routingorchestrator 204 can direct the data packet destined for the destinationnode to the particular candidate next-hop node 208A-208N.

FIG. 2B is a block diagram of another example networking environment200B in accordance with some implementations. In this example, thenetworking environment 200B includes a source node 202 that implementsan attestation routing orchestrator 202A. In some implementations, theattestation routing orchestrator 202A can be similar to, or adaptedfrom, the attestation routing orchestrator 204 in FIG. 2A.

The source node 202 can include one or more processors 202B. In someimplementations, the one or more processors 202B can provide processingresources for generating a confidence scores for the candidate next-hopnodes 208A-208N. In some implementations, the one or more processors202B can provide processing resources for selecting a particularconfidence score, from the confidence scores, that satisfies one or moreselection criteria.

In some examples, the source node 202 can include a memory 202C. Thememory 202C can be, for example and without limitation, a non-transitorymemory, such as RAM (random-access memory), ROM (Read-only memory), etc.The memory 202C can store the data, such as the packet destined for thedestination node 216. In some implementations, the memory 202C can storea trusted state or image vector obtained from the verifier system 206.In some implementations, the memory 202C can store attestation states orvectors obtained from the candidate next-hop nodes 208A-208N andoptionally attestation states or vectors obtained from the candidatesecond hop nodes 210A-210N and/or the candidate N-hop nodes 212A-212N.

The source node 202 can also include a network interface 202D forobtaining, receiving, and transmitting the data packets and states orvectors.

In some implementations, the source node 202 can select and direct adata packet to a particular candidate next-hop node based a trustedstate or image vector and the attestation states or vectors.

FIG. 2C is a block diagram of another example networking environment200C in accordance with some implementations. In this example, one ormore of the candidate next-hop nodes 208A-208N can relay a trusted stateor image vector from the verifier system 206 to the source node 202. Insome implementations, the attestation routing orchestrator 202A can besimilar to, or adapted from, the attestation routing orchestrator 204 inFIG. 2A and/or the attestation routing orchestrator 202A in FIG. 2B.

In some implementations, the verifier system 206 can sign the trustedstate or image vector and provide the signed trusted state or imagevector to a particular candidate next hop node, which in turn canprovide the signed trusted state or image vector to the source node 202.In some implementations, having the particular candidate next hop nodeprovide the signed trusted state or image vector can reduce attestationtime (e.g., the time to determine trustworthiness of the particularcandidate next hop node) because the source node 202 may not need tocontact a remote node (verifier system 206). In some implementations,attestation time can be further reduced because a single attestationprocess (e.g., the verifier system 206 signing the trusted state orimage vector) facilitates the attesting of multiple source nodes. Inother words, trusted states or image vectors may not be generated andevaluated on a per source node basis.

Moreover, in implementations in which the source node 202 is notconnected to the verifier system 206 (e.g., link down), obtaining thetrusted state or image vector from the particular candidate next hopprovides an alternative mechanism for node attestation. In someimplementations, the verifier system 206 appends a time-stamped responseto the trusted state or image vector as part of the signing process,which can be referred to as stapling. Consequently, the source node 202may not contact the verifier system 206 in order to attest a particularcandidate next hop node.

FIG. 2D is a block diagram of an example controller-orchestratedattestation-based routing 200D, in accordance with some implementations.In some examples, the source node 220 is similar to, or adapted from,the source node 202 in FIG. 2A. As illustrated in FIG. 2D, theattestation routing orchestrator 204 is separate from, but coupled(e.g., connected) to, the source node 220. In some examples, theattestation routing orchestrator 204 can include a controller withknowledge of the network 214 that includes the candidate next-hop nodes208A-N and optionally the candidate second-hop nodes 210A-N and/or thecandidate N-hop nodes 212A-N.

For example, in some implementations, the attestation routingorchestrator 204 can be a network management system (NMS). As anotherexample, in some implementations, the attestation routing orchestrator204 can be an intent-based networking system, such as Cisco's DigitalNetwork Architecture (DNA). As yet another example, in someimplementations, the attestation routing orchestrator 204 can be awireless LAN controller (WLC), and the candidate next-hop nodes208A-208N and optionally the candidate second hop nodes 210A-N and/orthe candidate N-hop nodes 212A-N can be networking devices such asaccess points, user devices, switches, routers, firewalls, etc.

The attestation routing orchestrator 204 can obtain attestation data(e.g., canary stamps) from the candidate next-hop nodes 208A-208N. Eachof the candidate next-hop nodes 208A-208N can be included within arespective route between the source node 220 and a destination node(e.g., 214). In some implementations, the respective routes areindependent of each other.

The attestation routing orchestrator 204 can determine confidence scoresbased on the attestation data. For example, in some cases, each of theconfidence scores can be based on a comparison between a correspondingone of the attestation data and a trusted state or image vector. In someimplementations, the attestation routing orchestrator 204 can obtain thetrusted state or image vector from the verifier system 206.

In some examples, the attestation routing orchestrator 204 can obtainattestation data from candidate second-hop nodes (e.g., 210A-N) and/orcandidate N-hop nodes (212A-N). Each of the candidate second-hop nodesand/or the candidate N-hop nodes can be included within a respectiveroute between a corresponding one of the candidate next-hop nodes208A-208N and the destination node. Moreover, each of the confidencescores can additionally be based on a comparison between a correspondingone of the attention data and the trusted state or image vector incombination with a comparison between another corresponding one of theattestation data from the candidate next-hop nodes 208A-N and thetrusted state or image vector.

The attestation routing orchestrator 204 can select, from the confidencescores, a particular confidence score that satisfies one or moreselection criteria. The particular confidence score is associated with aparticular candidate next-hop node of the candidate next-hop nodes208A-208N.

The attestation routing orchestrator 204 can directs, to the particularcandidate next-hop node, a data packet destined for the destinationnode. For example, in some cases, the attestation routing orchestrator204 can provide attested route information (e.g., validated canary stampdata, security measurements, etc.) to an attestation route manager 224Dof the source node 220 in order to facilitate the source node 220sending the data packet to the particular candidate next-hop node. Theattested route information can be indicative of the trustworthiness ofeach of the candidate next-hop nodes 208A-208N.

For example, in some implementations, the attested route informationincludes an identifier (e.g., an IP address, a MAC address, an SSID,etc.) identifying a secure candidate next-hop node of the candidatenext-hop nodes 208A-208N. In this example, the source node 220 canprovide the data packet based on the identifier in order to route thedata packet to the secure, particular candidate next-hop node.

As another example, in some implementations, the attested routeinformation can include confidence scores associated with the candidatenext-hop nodes 208A-208N. In this example, the attestation route manager224D can select a particular candidate score based on one or moreselection criteria. Moreover, the attestation route manger 224D canprovide the data packet to the particular next-hop node associated withthe particular candidate score. In some examples, the attestationrouting orchestrator 204 can cease to direct additional data packets tothe particular candidate next-hop node in response to determining thatthe particular confidence score falls below a confidence threshold.

In some cases, the source node 220 can include one or more processors224A. The one or more processors 224A can provide processing resourcesfor managing attested route information obtained from the attestationrouting orchestrator 204. The source node 220 can also include a memory224B. The memory 224B can include, for example, a non-transitory memorysuch as RAM, ROM, etc. In some examples, the memory 224B can store datasuch as the obtained attested route information and data packets to betransmitted. The source node 220 can also include a network interface224C for obtaining the attested route information and sending/receivingother data.

In some cases, whether a network device has been compromised can bedetermined based on indicators associated with the network device andtime information. The indicators can include, but are not limited to, aset of security measurements or evidence footprints which indicatewhether a particular device is compromised. Such indicators can comefrom one or more sources such as, for example and without limitation.TPM, canary stamps, Syslog, YANG Push, EEM, peer devices, trafficcounters, and other sources. Visibility can be a method of identifying acompromise in a timely manner.

When there are no indicators (i.e., no security measurements orfootprints available), the probability of a device being compromise canbe a function of the time which has passed since a last validation thatthe device is in a known good state. In some cases, with the foregoingindicators, a formula can be provided for estimating probability orchance of a compromise on any given device operating within a network.

For example, P_v₁ can be defined as a probability for compromise of type1 when there is a specific set of events/signatures existing whichcorrespond to the compromise. P_v₂ can be defined as probability forcompromise of type 2 and P_v_(x) can be defined as probability forcompromise of type x. Assuming each of these compromises (P_v₁ throughP_v_(x)) are independent, the following equation can provide theprobability of a compromise based on recognized signatures (P_v):P_v=1−((1−P_v ₁)(1−P_v ₂)(1−P_v _(x)))  Equation (1).

Other type of equations can be used instead of, or in conjunction with,equation (1) when there are interdependencies between different types ofevaluated compromises (P_v₁, P_v₂, P_v_(x)).

Furthermore, in some cases, a given probability (e.g., P_v₁-P_v_(x)) canbe determined based on evidence of events from a device for which theprobability of a compromise is being calculated (e.g., via equation (1))and/or evidence obtained from one or more devices adjacent to the devicefor which the probability of a compromise is being calculated (e.g., viaequation (1)).

In some cases, a probability that an invisible compromise has occurredat a device in the deployment environment can be expressed by theequation:P _(i)=1−((1−chance of invisible compromise in time period t){circumflexover ( )}number of t intervals since a last verification of agood/uncompromised system state)  Equation (2).

Effectively knowing P_(i) can imply that an operator knows the half-lifewhich should be expected before a device should be consideredcompromised independently of any concrete evidence. It should be notedthat a probability of an invisible compromise does not have to bestatic. Real-time modification based on current knowledge ofviruses/attacks may be allowed.

With formulates for visible and invisible factors as described above(equation (1) and equation (2)), an overall probability of a compromisefor a given device may be given by:P _(c)=1−((1−P _(v))*(1−P _(i)))  Equation (3).

Equation (3) provides an indicator of trustworthiness of a given device.This metric considers both time-based entropy and any available evidencewhich can be correlated to known compromises.

If P_(c) can be calculated (or roughly estimated), various functions canbe efficiently prioritized. For example, a controller may schedule whento do deeper validation (or perhaps direct refresh) of a device. Thisscheduling could include determining when to perform active checks tovalidate device memory locations (locations possibly containingexecutable code which might have been compromised). These can be used toreturn the system to a known good state (and reset the entropy timer).Local configuration repositories can be refreshed based on evidence ofsecurity/trustworthiness issues underway, rather than being based juston time. Beyond the scheduling of system checks, there can be forwardingimplications based on the value of P_(c). For example, routing orswitching behavior might be adjusted/impacted based on the relativetrustworthiness of a remote device. Where a higher P_(c) values exist,sensitive data traffic flows can be routed around that device.

As a further advantage of the present disclosure, it should be notedthat encryption alone may be insufficient to protect sensitive flowssince there are scenarios where even the fact that a flow is occurringbetween endpoints might be considered information to be protected (e.g.,in a battlefield).

FIG. 2E illustrates an example flow 200E for providing proof of packettransit through uncompromised nodes. In this example, the source node230 first sends (232) a packet destined to the destination node 216. Thesource node 230 can be similar to, or adapted from, source node 202, 220shown in FIGS. 2A, 2B, and 2C respectively.

The packet from the source node 230 is received by a next-hop node 208Aalong a route to the destination node 216. When the next-hop node 208Areceives the packet, it can add (234) canary stamp data to the packet.In some examples, the next-hop node 208A can include the canary stampdata in an IOAM data field on the packet. For example, in someimplementations, the next-hop node 208A can add the canary stamp data inan IOAM data field as an IOAM Trace option data element which can beused to carry the canary stamp data in the packet. In otherimplementations, the next-hop node 208A can add the canary stamp data ina new IOAM POT (proof-of-transit) data field which can be used to carrythe canary stamp data in the packet.

In other examples, the next-hop node 208A can include the canary stampdata in an Inband Network Telemetry (INT) header in the packet, anInband Flow Analyzer (IFA) header in the packet, or a header associatedwith an In-situ Flow Information Telemetry (IFIT) service used totransmit the packet.

The canary stamp data added to the packet can be used to verify or provethat the next-hop node 208A is a trusted or uncompromised node. Forexample, a receiving device, such as a verifier system (e.g., 206) or anode along the path of the packet, can analyze the canary stamp datacarried in the packet to assess whether the next-hop node 208A istrustworthy and/or compromised. The canary stamp data can includesecurity measurements taken at the next-hop node 208A or a hash/digestof the security measurements. The security measurements can evidence thetrustworthiness or integrity state of the next-hop node 208A. Forexample, the security measurements can include information about acurrent state of hardware, software, firmware, a runtime environment,etc., at the next-hop node 208A.

Such information can indicate whether the next-hop node 208A has beencompromised (e.g., hacked, attacked, accessed/modified withoutpermission, etc.); whether the next-hop node 208A has any unauthorizedor untrusted hardware or software components; whether a state (e.g.,firmware, hardware, software, boot files, sequence of loaded software,runtime environment, etc.) of the next-hop node 208A has been modifiedsince deployment and/or a previous known state, which could indicatethat the next-hop node has been compromised; etc. Non-limiting examplesof security measurements can include a hardware state or integritymeasurement, a runtime state or integrity measurement, a firmware stateor integrity measurement, a software integrity measurement, informationidentifying what software has been loaded at the node, informationidentifying a sequence of software loaded at the node, any operatingsystem changes at the node, any application log entries, an identity ofthe node, and/or any information that can be measured/captured todetermine whether the node has been compromised and/or whether the nodehas had any unverified/suspicious changes.

In some examples, the security measurements can be obtained by acryptoprocessor on the next-hop node 208A. The cryptoprocessor canprovide secure storage and measurement capabilities for the next-hopnode 208A. For example, the cryptoprocessor can measure what softwarewas loaded at the next-hop node 208A during and/or since it was booted.As new software is loaded at the next-hop node 208A, the cryptoprocessorcan measure the new loaded software. The cryptoprocessor in this examplecan thus obtain a picture of what software and files have been loaded atthe next-hop node 208A and a particular sequence in which the softwareand files were loaded. The loaded software and files and the loadsequence can be used to detect any unexpected or unusual software andfiles loaded in the next-hop node 208A or an unexpected or unusual loadsequence, which can be used to determine whether the next-hop node 208Ais trustworthy and/or has been compromised.

In some implementations, the cryptoprocessor can provide the rawsecurity measurements for use as part (or all) of the canary stamp data.In other implementations, the cryptoprocessor can hash the securitymeasurements and provide the hash result for use as part (or all) of thecanary stamp data. Moreover, in some cases, the cryptoprocessor can signthe security measurements or a hash of the security measurements tovalidate the security measurements and/or protect the informationagainst tampering (236).

In some cases, the canary stamp data can also include a time or countervalue which can be used to indicate a freshness of the canary stampdata. For example, the next-hop node 208A can include a time or countervalue in the canary stamp data to indicate when the securitymeasurements associated with the canary stamp data were taken and/or aninterval between the time when the current security measurements weretaken and the time when previous security measurements were taken.

The freshness information can allow a device reviewing or verifying thecanary stamp data to determine whether the associated securitymeasurements are sufficiently fresh to be reliable and/or to prevent amalicious actor from simply re-using old data to trick a verifyingdevice. In some cases, the time or counter value can include, forexample and without limitation, one or more TPM counters (e.g., clock,reset, restart), a timestamp, or a TUDA time-synchronization token.

In some cases, the canary stamp data can also include one or more noncevalues. The one or more nonce values can be used to insert randomnessinto the canary stamp data to prevent potential replay attacks. In someexamples, the one or more nonce values can be provided to the next-hopnode 208A by a remote or centralized system, such as the verifier system206, for example. The remote or centralized system can provide suchnonce values to nodes for use in respective canary stamp data in orderto insert randomness into such data, as previously described. In suchexamples, since the nonce values used in canary stamp data are providedand known by the remote or centralized system, the remote or centralizedsystem (and/or a separate verifier system) knows what the values in thecanary stamp data and/or the nonce values in the canary stamp datashould be or are expected to be, which can allow the remote orcentralized system (and/or the separate verifier system) to validatesuch data and prevent replay attacks.

In some cases, in addition to adding the canary stamp data to thepacket, the next-hop node 208A can also cryptographically sign thecanary stamp data. In some examples, the next-hop node 208A can signsome or all of the canary stamp data using an encryption algorithmand/or an encryption key, such as a public key provided by a remote orcentralized system (e.g., verifier system 206). Moreover, in someexamples, the next-hop node 208A can sign some or all of the canarystamp data using a cryptoprocessor on the next-hop node 208A, aspreviously explained.

Once the next-hop node 208A has added the canary stamp data to thepacket, the next-hop node 208A can send (238) the packet with the canarystamp data to the second-hop node 210A. In some implementations, thesecond-hop node 210A can receive the packet and add/update (540) thecanary stamp data in the packet to include canary stamp data associatedwith the second-hop node 210A. For example, in some cases, thesecond-hop node 210A can add additional canary stamp data to the packetso the packet includes canary stamp data from both the next-hop node208A and the second-hop node 210A. Similar to the canary stamp dataassociated with the next-hop node 208A, the additional canary stamp dataassociated with the second-hop node 210A can include securitymeasurements taken from the second-hop node 210A.

In other cases, the second-hop node 210A can update the canary stampdata in the packet with new canary stamp data representative of thecanary stamp data from the next-hop node 208A and canary stamp data fromthe second-hop node 210A. To illustrate, in some cases, the canary stampdata in the packet received by the second-hop node 210A can include acanary stamp digest from the next-hop node 208A. The canary stamp digestfrom the next-hop node 208A can include a hash of the securitymeasurements taken at the next-hop node 208A. The second-hop node 210Acan then create a hash of security measurements taken from thesecond-hop node 210A to create a canary stamp for the second-hop node210A. The second-hop node 210A can then update or replace the canarystamp data in the packet with a new canary stamp digest, which can be adigest of the canary stamp digest from the next-hop node 208A and thecanary stamp of the second-hop node 210A (e.g., the hash of the securitymeasurements taken from the second-hop node 210A).

This way, the new canary stamp digest included in the packet by thesecond-hop node 210A can represent both the canary stamp digest (and thesecurity measurements) from the next-hop node 208A and the canary stampdigest (and the security measurements) from the second-hop node 210A. Insome examples, each hop that receives the packet can similarly updatethe canary stamp data in the packet to include a new canary stampdigest. The final version of the canary stamp digest in the packet tothe destination node 216 can thus reflect or represent the canary stampdigest (and the security measurements) from each node along the path ofthe packet. A verifier system (e.g., 206) or an inline node can comparethat final version of the canary stamp digest in the packet with anexpected canary stamp digest calculated based on expected securitymeasures for each of the nodes in the path, to validate (or invalidate)the final version of the canary stamp digest.

In some cases, the second-hop node 210A can also sign (242) some or allof the canary stamp data added or updated by the second-hop node 210A,as previously explained. The second-hop node 210A can then send (244)the packet with the new or updated canary stamp data, along the path tothe N-hop node 212A. The N-hop node 212A can receive the packet andvalidate (246) the canary stamp data in the packet.

In some examples, when validating the canary stamp data, the N-hop node212A can check any signatures, nonce values, and/or time or countervalues in the canary stamp data to verify that the canary stamp data hasnot been tampered with and is sufficiently fresh to be reliable.Moreover, in some cases, to validate the canary stamp data, the N-hopnode 212A can compare the canary stamp data in the packet with anexpected canary stamp data value(s) calculated based on the nodestraversed by the packet and associated security measurements (orexpected security measurements).

For example, the N-hop node 212A can create a digest of a known orprevious state (e.g., known or previous security measurements) of eachnode traversed by the packet and compare the resulting digest with acanary stamp digest in the packet. If the digests match, the N-hop node212A can determine that the nodes traversed by the packet have not havehad changes in state and/or are not compromised. In some cases, if thedigests do not match, the N-hop node 212A can check the securitymeasurements from one or more nodes along the path of the packet todetermine which node has had a change in state and/or is potentiallycompromised.

If the N-hop node 212A determines that a node is compromised or isunable to verify that the node is not compromised, the N-hop node 212Areport such findings or otherwise trigger a remediation action to avoida potential compromise of data and/or network resources. For example, ifa node is determined to be compromised or its trustworthiness/integritycannot be confirmed, a policy can be implemented on the network to avoidrouting traffic through that node until that node can be returned to anormal state or confirmed to not be compromised. As another example, ifa node is determined to be compromised or its trustworthiness/integritycannot be confirmed, the node can be powered off or removed from thenetwork until the node can be returned to a normal state or confirmed tonot be compromised.

In other cases, to validate the canary stamp data, the N-hop node 212Acan check security measurements included in the canary stamp data andassociated with each node along the path of the packet to determine ifany of the nodes have had a change in state and/or have unusual,unexpected, and/or potentially problematic security measurements. Forexample, the N-hop node 212A can compare a security measurement(s) fromeach node with an expected security measurement(s) or previous knowngood security measurement(s) from each node to determine if any node hashad a change in state and/or is potentially compromised.

In some cases, to validate the canary stamp data, the N-hop node 212Acan check if the canary stamp data matches a previous version of thecanary stamp data to determine if any state changes have occurred on anyof the nodes along the path of the packet. The N-hop node 212A can alsocheck a nonce and/or time or counter value to verify that the canarystamp data is fresh and is not part of a replay attack. If the canarystamp data matches the previous version of the canary stamp data, thecanary stamp data is fresh, and there are no indications of a possiblereplay attack, the N-hop node 212A can determine that none of the nodeshave had a change in state and validate the canary stamp data. Thevalidated canary stamp data can indicate that the nodes along the pathof the packet are not currently compromised.

The N-hop node 212A can then send (248) the packet to the destinationnode 216. In some cases, prior to sending the packet to the destinationnode 216, the N-hop node 212A can add/update the canary stamp data toinclude canary stamp data from the N-hop node 212A and/or reflectsecurity measurements from the N-hop node 212A. The N-hop node 212A cansend the packet to the destination node 216 with the current version ofthe canary stamp data to allow the destination node 216 itself verifythat the packet traversed only through uncompromised nodes. Moreover, insome cases, prior to sending the packet, the N-hop node 212A can alsosign the canary stamp data as previously described.

In some cases, in validating the canary stamp data as described herein,the N-hop node 212A can determine or verify whether the packet traversedthrough uncompromised nodes or whether the packet traversed through oneor more compromised nodes. Moreover, in some implementations, inaddition to, or in lieu of, validating the canary stamp data, the N-hopnode 212A can send the packet with the canary stamp data to a separatedevice for validation/verification. For example, the N-hop node 212A cansend the packet with the canary stamp data to a verifier system (e.g.,206) to have the verifier system validate the canary stamp data andconfirm or determine that the packet has or has not traversed throughcompromised and/or uncompromised nodes.

In some cases, every hop in the chain of hops traversed by the packetcan provide canary stamp data and sign such canary stamp data so thatall hops in the chain can be verified to be uncompromised. For example,in addition to the nodes along the path of the packet providing orupdating canary stamp data as previously described, if the packet issent to a separate verifier system for verification, the verifier systemcan similarly modify the packet to add or update canary stamp data toinclude or reflect its own canary stamp data (and/or securitymeasurements) and prove that the verifier system is not compromised.

While FIG. 2E shows the canary stamp data in the packet being validatedby the last hop (e.g., the N-hop node 212A) before the destination node216, it should be noted that the canary stamp data can also oralternatively be validated by one or more other nodes in the path and/ora remote verifier system (e.g., 206). For example, in some cases, thecanary stamp data in the packet can be validated by a centralizedverifier system (e.g., at each hop or at one or more hops along thepath) and/or by one or more intermediate nodes along the path (e.g., asthe packet traverses those nodes). In FIG. 2E, the validation performedby the N-hop node 212A is one illustrative example provided forexplanation purposes.

In each case in the discussion above, the introduction of the use ofadding canary stamp data to a revised version of the MACsec protocol orthe MKA protocol can apply.

FIG. 2F illustrates another example flow 200F for providing proof ofpacket transit through uncompromised nodes, where a verifier system 206verifies and signs canary stamp data at each hop along the path of thepacket. It should be noted that this is one illustrative exampleimplementation provided for explanation purposes, and in other examplesthe verifier system 206 may only verify and sign canary stamp data atone or more hops along the path of the packet.

In this example, the source node 250 first sends (252) a packet for thedestination node 216 to the next-hop node 208A. The next-hop node 208Areceives the packet and adds and signs (254) canary stamp data generatedbased on security measurements taken at the next-hop node 208A (e.g.,via a cryptoprocessor). The next-hop node 208A can add canary stamp datacontaining the security measurements or a digest of the canary stampdata (e.g., the security measurements), as previously explained.

The next-hop node 208A can then send (256) the packet with the canarystamp data to the verifier system 206 for validation. In some examples,the verifier system 206 can be a centralized system, such as acentralized server or controller, configured to analyze and verifycanary stamp data from nodes. In other examples, the verifier system 206can be a distributed system including multiple verifiers configured toanalyze and verify canary stamp data from nodes.

The verifier system 206 can receive the packet from the next-hop node208A and verify and sign (258) the canary stamp data in the packet. Insome cases, the verifier system 206 can check that the canary stamp datain the packet from the next-hop node 208A is fresh (e.g., based on anonce and/or a time value or counter on the packet) and use the canarystamp data to verify that the next-hop node 208A is not compromised. Theverifier system 206 can also check that the canary stamp data in thepacket is not part of a replay attack. For example, the verifier system206 can verify that the canary stamp data is not simply a copy of oldcanary stamp data added to the packet by an attacker or compromisedcomponent to trick the verifier system 206 into determining that thecanary stamp data is valid and the next-hop node 208A has not beencompromised. In some examples, the verifier system 206 can use, or checkfor, nonce values that introduce randomness into the data, to identifyand/or protect against such replay attacks.

In some cases, when verifying and signing the canary stamp data in thepacket, the verifier system 206 can add its own signed canary stamp datato the packet or update the canary stamp data with its own canary stampdata as previously explained. This way, every hop that processes thepacket can be verified, and other nodes can verify that the verifiersystem 206 itself is not compromised.

The verifier system 206 can then send (260) the packet with the canarystamp data back to the next-hop node 208A. At this point, the canarystamp data in the packet received by the next-hop node 208A is validatedand signed by the verifier system 206. The next-hop node 208A can thensend (262) the packet with the canary stamp data to the second-hop node210A. The canary stamp data in the packet can include the canary stampand signature from the next-hop node 208A. In some cases, the canarystamp data in the packet can also reflect canary stamp data andsignature data from the verifier system 206, as previously explained.

The second-hop node 210A then add/update and sign (264) the canary stampdata in the packet. In some examples, the second-hop node 210A can addnew canary stamp data generated based on security measurements taken atthe second-hop node 210A. Here, the packet can include the canary stampdata from the next-hop node 208A and the new canary stamp data from thesecond-hop node 210A. In other examples, the second-hop node 210A cantake the canary stamp data from the next-hop node 208A and update it toalso reflect new canary stamp data (and/or security measurements) fromthe second-hop node 210A.

For example, the second-hop node 210A can hash the security measurementstaken at the second-hop node 210A and generate a digest based on a hashvalue or digest from the next-hop node 208A (e.g., the canary stamp datafrom the next-hop node 208A) and the hash of the security measurementstaken at the second-hop node 210A. To illustrate, the second-hop node210A can generate a new canary stamp digest as follows: New canary stampdigest=Digest of (canary stamp data from the next-hop node208A∥hash(canary stamp data from the second-hop node 210A)).

In some cases, the second-hop node 210A can also implement a nonce valueand/or a time value or token when calculating the new canary stamp data.For example, in some cases, the second-hop node 210A can generate thenew canary stamp digest as follows: New canary stamp digest=Digest of(canary stamp data from the next-hop node 208A∥hash(canary stamp datafrom the second-hop node 210A∥PPN)), where PPN represents a per-packetnonce (PPN) assigned to the current packet and which changes per packet.As another example, in some cases, the second-hop node 210A can generatethe new canary stamp digest as follows: New canary stamp digest=Digestof (canary stamp data from the next-hop node 208A∥hash(canary stamp datafrom the second-hop node 210A∥TUDA time-synchronization token associatedwith the second-hop node 210A)), where the TUDA time-synchronizationtoken is provided by a central timestamp authority.

In some cases, when adding/updating canary stamp data, the second-hopnode 210A can concatenate or combine canary stamp data from the next-hopnode 208A and the second-hop node 210A. For example, in some cases, thecanary stamp data from the next-hop node 208A can include one or moresecurity measurements taken at the next-hop node 208A. To add/updatecanary stamp data, the second-hop node 210A can concatenate or combinesuch security measurements with one or more other security measurementstaken at the second-hop node 210A. This can result in canary stamp datathat includes and/or reflects security measurements from both thenext-hop node 210A and the second-hop node 210A.

Once the added/updated and signed the canary stamp data, the second-hopnode 210A can send (624) the packet with the new/updated canary stampdata to the verifier system 206. The verifier system 206 can then verifyand sign (268) the canary stamp data as previously explained. Afterverifying and signing the canary stamp data, the verifier system 206 cansend (270) the packet with the canary stamp data back to the second-hopnode 210A. In some cases, when verifying the canary stamp data, theverifier system 206 can also add/update the canary stamp data with itsown canary stamp data generated based on security measurements taken atthe verifier system 206, and sign the result prior to sending the packetwith the canary stamp data to the verifier system 206.

The second-hop node 210A can receive the packet with the canary stampdata and send (272) it to the N-hop node 212A. The N-hop node 212A canreceive the packet with the canary stamp data and add/update and sign(274) the canary stamp data as previously described with respect to thesecond-hop node 210A. The N-hop node 212A can then send (276) the packetwith the new or updated canary stamp data to the verifier system 206.The verifier system 206 can receive the packet with the canary stampdata from the N-hop node 212A, and validate (278) the canary stamp datain the packet.

When validating the canary stamp data, the verifier system 206 can usethe canary stamp data in the packet to verify that none of the nodes(e.g., 208A. 210A, 212A) traversed by the packet are compromised. Theverifier system 206 can verify the integrity or trustworthiness of eachof the nodes based on the value(s) in the canary stamp data (e.g., theassociated security measures, the associated digest values, etc.). Sincethe canary stamp data can contain security measures from each of thenodes or reflect security measures from each of the nodes (e.g., thecanary stamp data can be updated at each hop based on security measuresat that hop or a digest of security measures at that hop), the canarystamp data can provide an indication of the state andintegrity/trustworthiness of each hop in the chain, which the verifiersystem 206 can use to validate (or invalidate) the canary stamp data inthe packet.

In some implementations, when validating the canary stamp data, theverifier system 206 can also verify that the canary stamp data is fresh(e.g., was generated within a certain period of time from the time itwas received by the verifier system 206) and/or that the canary stampdata is not a replay attack. The verifier system 206 can make suchdeterminations based on timing information (e.g., one or more TUDAtime-synchronization tokens, a time or counter value such as a TPMcounter value, etc.) included in the canary stamp data and/or associatedwith the nodes in the path, one or more nonce values used to introducerandomness in the canary stamp data, etc.

Moreover, in some examples, when validating the canary stamp data, theverifier system 206 can also add its own signed canary stamp data to thepacket or update the canary stamp data in the packet based on its owncanary stamp data. Once the verifier system 206 has validated the canarystamp data, the verifier system 206 can send (280) the packet with thevalidated canary stamp data back to the N-hop node 212A, which can thensend (282) the packet to the destination node 216.

In some cases, rather than sending the packet to the N-hop node 212A,the verifier system 216 can deliver the packet to the destination node216, thereby reducing the amount of traffic (e.g., by eliminating thecommunication of the packet back to the N-hop node 212A for subsequentdelivery to the destination node 216). Moreover, in some cases, thepacket delivered (e.g., by the N-hop node 212A or the verifier system206) to the destination node 216 can include the current version of thecanary stamp data to allow the destination node 216 to perform its ownverification that the packet traversed only through uncompromised nodes.

Further, an attestor, e.g. a node or a verifier, can use random numbers,otherwise pseudo-random numbers, created by peers and/or the attestor togenerate and verify attestation information. Specifically, the attestorcan accumulate random numbers from one or more layer 2 peers. The randomnumbers can be accumulated from the peers over a specific amount oftime, e.g. a short duration of time. In turn, the random numbers can becombined into a number through an applicable technique, e.g. a Bloomfilter. This number can serve as a nonce for a cryptoprocessor forgenerating a result. As follows, the layer 2 peers, potentiallyincluding the attestor, can use the result created by thecryptoprocessor, to verify/validate that their corresponding providedrandom number was used in generating the nonce ultimately used by thecryptoprocessor to create the result. In turn, the layer 2 peers,potentially including the attestor, can generate verified attestationinformation based on the random numbers generated by the peers, thenonce created from the random numbers, and/or the result created by thecryptoprocessor from the nonce.

MKA Protocol Expansion for Attestation Data

Having discussed the canary stamp or attestation data and processesabove, the disclosure returns to the application of the canary stamp orattestation data in the MKA protocol. The MKA offers the ability forextents ability of the peer exchange. A MACsec station 102, 106 coulddeclare itself as having attestation trust capabilities. To furtherextend the capabilities, the system can include an option for theoperator that manages two stations to establish MACsec peeringcapabilities, they must both have, for example, TPM capabilities withcanary stamps, or the MKA/MACsec session will not be established. Forthose nodes without the capabilities for TPM and/or attestation, theoption would exist for “should” have to extend the MKA protocol to addsupport for attestation messages, MKA uses defined MKPDU (MACsec KeyAgreement Protocol Data Unit).

“parameter sets” for extending various functions within the MKAprotocol. To add attestation compelled capabilities within MKA, a new“attestation parameter set” (or the like) would be to find that wouldidentify the ability of two or more peers 102, 106 to transportattestation messages, and in line with EAPoL-MKA, would advertisecapabilities of the sending station 102. The EAPol is the EAP(Extensible Authentication Protocol) over LAN (Local Area Network).

The proposed concept can include attestation information as described asdescribed above in the canary stamp, as well as other relevant devicespecific capabilities derived from the TPM as the root of trust for thedevice. FIG. 3 illustrates an example amendment to increase the MKAversion identifier. A new attestation paramset 302 can be provided inthe overall protocol structure 300. Only after a successful validationof attestation paramset 302, with the potential peer be transitioned toa live peer mode in which the communication can occur. The transitioncan be from a potential mode in which a node has the potential tocommunicate with another mode but the communication will not occur untilthe attestation data and/or identity data is confirmed. The attestationparamset 302 received from an already live peer can be ignored in oneaspect. In another aspect, for backward capability, the attestationvalidation can be controlled by a local policy parameter such as byallowing MKA peers running with a certain version of the protocol orlower. In one aspect, a local node does not support the ability toevaluate the attestation paramset. In such a case, local policies maycause the remote node not to prepare and send the attestation paramsetbefore a communication.

In another aspect, if the MACsec protocol is programmed by a controlplain protocol which doesn't support the attestation or if the SAK isdirectly programmed or for continuous attestation for back piggybackedinto selected data packets, the MACsec can enforce the attestation ifenabled. The system can transmit the attestation header as part of anewly defined SecTAG extension 400 as shown in FIG. 4A. The new headerwould include an attestation component which carries the attestationheader/data that would be part of the MACsec header.

FIG. 4B illustrates 402 the MACsec TCI and AN encoding. The TCI bit 8(version) (0 is the version shown) would be updated such that theversion would be shown as v=1 and a new section extensions header wouldbe provided in the new version.

In one aspect, assume as is shown in FIG. 1, that one peer 102 issending attestation information and another peer 106 is also sendingattestation information. Assume that two routers in the network 104 willalso send attestation information. Through the principles disclosedherein, the peer 102 may continue to send attestation information untilit has properly received and confirmed through the attestation datadefined herein, the other node 106 and the two routers in the network104. Then it can stop sending its attestation data and can move to livepeer mode and communication with the other node 106. The system willessentially confirm and validate each node or device in a communication.

FIG. 5 illustrates a method example. The method can include one or moreof receiving an attestation parameter associated with a first peer in apeer-to-peer communication (502), adding the attestation parameter to anMACsec Key Agreement (MKA) protocol key exchange (504), transmitting thekey exchange from the first peer to a second peer in the peer-to-peercommunication (506) and upon a validation of the attestation parameterby the second peer, enabling secure communication between the first peerand the second peer (508).

In one aspect a node that will evaluate a canary stamp in a MACsecprotocol needs to announce that it has the capability of performing suchanalysis. Such a node can transmit an advertisement that it is capableof evaluating the attestation parmset or canary stamp data. This can becalled an announcement paramset. Another device in the system that alsohas the capability of producing the canary stamp or similar data then,in response to the advertisement, will provide the data which can beintegrated or inserted into the MACsec protocol for establishing thesecure communication. There may also be local policies to one or more ofthe nodes that also need to be fulfilled or followed. For example, forevery MACsec installation, a policy may require that there is arevalidation of the attestation periodically, upon a triggering event,or based on some other parameter or event.

This disclosure adds an in-depth layer of attestation information toIEEE 802.1AE MACsec by leveraging the control plane key exchangeprotocol of the MKA protocol, extending the MKA protocol to supporttransporting attestation information or messages between two or moreMACsec stations. In another aspect, this disclosure extends the MACsecdata plane to support transporting attestation information between twoor more MACsec stations piggybacked into the data packets.

In one example, the use of the attestation parameters can be handled inthe control plane key exchange protocol of the MKA protocol. Theconfirmation of the attestation parameters in the control plane canalleviate the need for the continued or separate confirmation ofattestation parameters in the data plane using the MACsec. However,local policies may also require using the attestation parameters in thedata plane/MACsec as well.

Adding the attestation parameter to an MKA protocol key exchange furthercan include adding the attestation parameter to a SecTAG header of aMACsec protocol. In another aspect, the validation of the attestationparameter by the second peer causes the second peer to transition to alive peer mode. This can be a transition from a non-live mode or a downmode in which no secure communication is provided. The method canfurther include, after establishing the live peer mode for the secondpeer to engage in the secure communication, confirming the securecommunication via an exchange of a second MKA protocol key exchangehaving a second attestation parameter added thereto. The attestationparameter can also be configured in a new SecTAG extension header. Thenew SecTAG extension header can have the attestation parameter as partof the MACsec protocol. In this regard, the approach enables the use ofattestation parameters in the data plane which can further enhance theability of devices to confirm the integrity of other devices in thenetwork that are involved in a secure communication.

FIG. 6 illustrates an example network device 600 suitable forimplementing aspects of this disclosure. In some examples, the controlplane 310 and/or the SVP 318 may be implemented according to theconfiguration of the network device 600. The network device 600 includesa central processing unit (CPU) 604, interfaces 602, and a connection610 (e.g., a PCI bus). When acting under the control of appropriatesoftware or firmware, the CPU 604 is responsible for executing packetmanagement, error detection, and/or routing functions. The CPU 604preferably accomplishes all these functions under the control ofsoftware including an operating system and any appropriate applicationssoftware. The CPU 604 may include one or more processors 608, such as aprocessor from the INTEL X86 family of microprocessors. In some cases,processor 608 can be specially designed hardware for controlling theoperations of the network device 600. In some cases, a memory 606 (e.g.,non-volatile RAM ROM, etc.) also forms part of the CPU 604. However,there are many different ways in which memory could be coupled to thesystem.

The interfaces 602 are typically provided as modular interface cards(sometimes referred to as “line cards”). Generally, they control thesending and receiving of data packets over the network and sometimessupport other peripherals used with the network device 600. Among theinterfaces that may be provided are Ethernet interfaces, frame relayinterfaces, cable interfaces, DSL interfaces, token ring interfaces, andthe like. In addition, various very high-speed interfaces may beprovided such as fast token ring interfaces, wireless interfaces.Ethernet interfaces, Gigabit Ethernet interfaces, ATM interfaces. HSSIinterfaces, POS interfaces. FDDI interfaces, WiFi interfaces, 3G/4G/5Gcellular interfaces, CAN BUS, LoRA, and the like. Generally, theseinterfaces may include ports appropriate for communication with theappropriate media. In some cases, they may also include an independentprocessor and, in some instances, volatile RAM. The independentprocessors may control such communications intensive tasks as packetswitching, media control, signal processing, crypto processing, andmanagement. By providing separate processors for the communicationsintensive tasks, these interfaces allow the CPU 604 to efficientlyperform routing computations, network diagnostics, security functions,etc.

Although the system shown in FIG. 6 is one specific network device ofthe present technologies, it is by no means the only network devicearchitecture on which the present technologies can be implemented. Forexample, an architecture having a single processor that handlescommunications as well as routing computations, etc., is often used.Further, other types of interfaces and media could also be used with thenetwork device 600.

Regardless of the network device's configuration, it may employ one ormore memories or memory modules (including memory 606) configured tostore program instructions for the general-purpose network operationsand mechanisms for roaming, route optimization and routing functionsdescribed herein. The program instructions may control the operation ofan operating system and/or one or more applications, for example. Thememory or memories may also be configured to store tables such asmobility binding, registration, and association tables, etc. The memory606 could also hold various software containers and virtualizedexecution environments and data.

The network device 600 can also include an application-specificintegrated circuit (ASIC), which can be configured to perform routingand/or switching operations. The ASIC can communicate with othercomponents in the network device 600 via the connection 610, to exchangedata and signals and coordinate various types of operations by thenetwork device 600, such as routing, switching, and/or data storageoperations, for example.

FIG. 7 illustrates an example computing device architecture 700 of anexample computing device which can implement the various techniquesdescribed herein. The components of the computing device architecture700 are shown in electrical communication with each other using aconnection 705, such as a bus. The example computing device architecture700 includes a processing unit (CPU or processor) 710 and a computingdevice connection 705 that couples various computing device componentsincluding the computing device memory 715, such as read only memory(ROM) 720 and random access memory (RAM) 725, to the processor 710.

The computing device architecture 700 can include a cache of high-speedmemory connected directly with, in close proximity to, or integrated aspart of the processor 710. The computing device architecture 700 cancopy data from the memory 715 and/or the storage device 730 to the cache712 for quick access by the processor 710. In this way, the cache canprovide a performance boost that avoids processor 710 delays whilewaiting for data. These and other modules can control or be configuredto control the processor 710 to perform various actions. Other computingdevice memory 715 may be available for use as well. The memory 715 caninclude multiple different types of memory with different performancecharacteristics. The processor 710 can include any general purposeprocessor and a hardware or software service, such as service 1 732,service 2 734, and service 3 736 stored in storage device 730,configured to control the processor 710 as well as a special-purposeprocessor where software instructions are incorporated into theprocessor design. The processor 710 may be a self-contained system,containing multiple cores or processors, a bus, memory controller,cache, etc. A multi-core processor may be symmetric or asymmetric.

To enable user interaction with the computing device architecture 700,an input device 745 can represent any number of input mechanisms, suchas a microphone for speech, a touch-sensitive screen for gesture orgraphical input, keyboard, mouse, motion input, speech and so forth. Anoutput device 735 can also be one or more of a number of outputmechanisms known to those of skill in the art, such as a display,projector, television, speaker device, etc. In some instances,multimodal computing devices can enable a user to provide multiple typesof input to communicate with the computing device architecture 700. Thecommunications interface 740 can generally govern and manage the userinput and computing device output. There is no restriction on operatingon any particular hardware arrangement and therefore the basic featureshere may easily be substituted for improved hardware or firmwarearrangements as they are developed.

Storage device 730 is a non-volatile memory and can be a hard disk orother types of computer readable media which can store data that areaccessible by a computer, such as magnetic cassettes, flash memorycards, solid state memory devices, digital versatile disks, cartridges,random access memories (RAMs) 725, read only memory (ROM) 720, andhybrids thereof. The storage device 730 can include services 732, 734,736 for controlling the processor 710. Other hardware or softwaremodules are contemplated. The storage device 730 can be connected to thecomputing device connection 705. In one aspect, a hardware module thatperforms a particular function can include the software component storedin a computer-readable medium in connection with the necessary hardwarecomponents, such as the processor 710, connection 705, output device735, and so forth, to carry out the function.

For clarity of explanation, in some instances the present technology maybe presented as including individual functional blocks includingfunctional blocks including devices, device components, steps orroutines in a method embodied in software, or combinations of hardwareand software.

The present disclosure provides a proposed BFD low bandwidthimplementation which can reduce the BFD overhead buy as much as 50%which would provide a large gain for SDWAN (software-defined networkingin a wide-area network) customers.

In some embodiments the computer-readable storage devices, mediums, andmemories can include a cable or wireless signal containing a bit streamand the like. However, when mentioned, non-transitory computer-readablestorage media expressly exclude media such as energy, carrier signals,electromagnetic waves, and signals per se.

Methods according to the above-described examples can be implementedusing computer-executable instructions that are stored or otherwiseavailable from computer readable media. Such instructions can include,for example, instructions and data which cause or otherwise configure ageneral purpose computer, special purpose computer, or special purposeprocessing device to perform a certain function or group of functions.Portions of computer resources used can be accessible over a network.The computer executable instructions may be, for example, binaries,intermediate format instructions such as assembly language, firmware, orsource code. Examples of computer-readable media that may be used tostore instructions, information used, and/or information created duringmethods according to described examples include magnetic or opticaldisks, flash memory. USB devices provided with non-volatile memory,networked storage devices, and so on.

Devices implementing methods according to these disclosures can includehardware, firmware and/or software, and can take any of a variety ofform factors. Some examples of such form factors include general purposecomputing devices such as servers, rack mount devices, desktopcomputers, laptop computers, and so on, or general purpose mobilecomputing devices, such as tablet computers, smart phones, personaldigital assistants, wearable devices, and so on. Functionality describedherein also can be embodied in peripherals or add-in cards. Suchfunctionality can also be implemented on a circuit board among differentchips or different processes executing in a single device, by way offurther example.

The instructions, media for conveying such instructions, computingresources for executing them, and other structures for supporting suchcomputing resources are means for providing the functions described inthese disclosures.

Although a variety of examples and other information was used to explainaspects within the scope of the appended claims, no limitation of theclaims should be implied based on particular features or arrangements insuch examples, as one of ordinary skill would be able to use theseexamples to derive a wide variety of implementations. Further andalthough some subject matter may have been described in languagespecific to examples of structural features and/or method steps, it isto be understood that the subject matter defined in the appended claimsis not necessarily limited to these described features or acts. Forexample, such functionality can be distributed differently or performedin components other than those identified herein. Rather, the describedfeatures and steps are disclosed as examples of components of systemsand methods within the scope of the appended claims.

Claim language reciting “at least one of” a set indicates that onemember of the set or multiple members of the set satisfy the claim. Forexample, claim language reciting “at least one of A and B” means A, B,or A and B.

What is claimed is:
 1. A method comprising: receiving an attestationparameter associated with a first peer in a potential peer-to-peercommunication; adding the attestation parameter to a MACsec KeyAgreement (MKA) protocol key exchange, wherein adding the attestationparameter to the MKA protocol key exchange further comprises adding theattestation parameter to a SecTAG header of a MACsec protocol;transmitting the MKA protocol key exchange from the first peer to asecond peer in the potential peer-to-peer communication; and upon avalidation of the attestation parameter by the second peer, enablingsecure communication between the first peer and the second peer.
 2. Themethod of claim 1, wherein the validation of the attestation parameterby the second peer causes the second peer to transition to a live peermode.
 3. The method of claim 2, further comprising: after establishingthe live peer mode for the second peer to engage in the securecommunication, confirming the secure communication via an exchange of asecond MKA protocol key exchange having a second attestation parameteradded thereto.
 4. The method of claim 1, wherein one of the first peeror the second peer comprises a router in a network.
 5. The method ofclaim 1, wherein the attestation parameter is configured in a new SecTAGextension header.
 6. The method of claim 5, wherein the new SecTAGextension header having the attestation parameter is part of a MACsecheader.
 7. A system comprising: a processor; and a computer-readablestorage device storing instructions which, when executed by theprocessor, causes the processor to perform operations comprising:receiving an attestation parameter associated with a first peer in apotential peer-to-peer communication; adding the attestation parameterto a MACsec Key Agreement (MKA) protocol key exchange, wherein addingthe attestation parameter to the MKA protocol key exchange furthercomprises adding the attestation parameter to a SecTAG header of aMACsec protocol; transmitting the MKA protocol key exchange from thefirst peer to a second peer in the potential peer-to-peer communication;and upon a validation of the attestation parameter by the second peer,enabling secure communication between the first peer and the secondpeer.
 8. The system of claim 7, wherein the validation of theattestation parameter by the second peer causes the second peer totransition to a live peer mode.
 9. The system of claim 8, furthercomprising: after establishing the live peer mode for the second peer toengage in the secure communication, confirming the secure communicationvia an exchange of a second MKA protocol key exchange having a secondattestation parameter added thereto.
 10. The system of claim 7, whereinone of the first peer or the second peer comprises a router in anetwork.
 11. The system of claim 7, wherein the attestation parameter isconfigured in a new SecTAG extension header.
 12. The system of claim 11,wherein the new SecTAG extension header having the attestation parameteris part of a MACsec header.
 13. A computer-readable storage devicestoring instructions which, when executed by a processor, causes theprocessor to perform operations comprising: receiving an attestationparameter associated with a first peer in a potential peer-to-peercommunication; adding the attestation parameter to a MACsec KeyAgreement (MKA) protocol key exchange, wherein adding the attestationparameter to the MKA protocol key exchange further comprises adding theattestation parameter to a SecTAG header of a MACsec protocol;transmitting the key exchange from the first peer to a second peer inthe potential peer-to-peer communication; and upon a validation of theattestation parameter by the second peer, enabling secure communicationbetween the first peer and the second peer.
 14. The computer-readablestorage device of claim 13, wherein the validation of the attestationparameter by the second peer causes the second peer to transition to alive peer mode.
 15. The computer-readable storage device of claim 14,further comprising: after establishing the live peer mode for the secondpeer to engage in the secure communication, confirming the securecommunication via an exchange of a second MKA protocol key exchangehaving a second attestation parameter added thereto.
 16. Thecomputer-readable storage device of claim 13, wherein one of the firstpeer or the second peer comprises a router in a network.
 17. Thecomputer-readable storage device of claim 13, wherein the attestationparameter is configured in a new SecTAG extension header.